## Calculus: Early Transcendentals 8th Edition

$x=4$ This is a straight line with $x$-intercept 4.
$r=4sec\theta$ Since, $sec\theta=\frac{1}{cos \theta}$ $rcos \theta=4sec\theta\times cos \theta$ $rcos \theta=4$ To convert polar equation to Cartesian coordinates, we use the equations $rcos \theta=x$ and $rsin \theta=y$ Thus, $x=4$ This is a straight line with $x$-intercept 4.